SG-38MPRA-02 Specifications subject to change without notice.
13
REFRIGERANT LINES
General Refrigerant Line Sizing
1. The outdoor units are shipped with a full charge of R410A refrigerant. All charges, line sizing, and capacities are based on runs of 25 ft. (7.6 m).
For runs over 25 ft. (7.6 m), consult “Long Line Applications:” for the proper charge adjustments.
2. The minimum refrigerant line length between the indoor and outdoor units is 10 ft. (3 m).
3. Refrigerant lines should not be buried in the ground. If it is necessary to bury the lines, not more than 36 in (914 mm) should be buried. Provide a
minimum 6 in (152 mm) vertical rise to the service valves to prevent refrigerant migration.
4. Both lines must be insulated. Use a minimum of 1/2 in. (12.7 mm) thick insulation. Closed-cell insulation is recommended in all long line
applications.
5. Special consideration should be given to isolating the interconnecting tubing from the building structure. Isolate the tubing so vibration or noise is
not transmitted into the structure.
IMPORTANT: Both refrigerant lines must be insulated separately.
Table 12 lists the maximum allowed lengths.
Table 12 — Piping and Refrigerant Information
Long Line Applications:
1. No change in line-set diameter size is required.
2. Add refrigerant per the “Additional Charge Table”.
Table 13 — Additional Charge Table
SYSTEM SIZE
9K (208-230V) 12K (208-230V) 18K (208-230V) 24K (208-230V)
Piping
Min. Piping Length
ft. (m)
9.8 (3)
9.8 (3)
9.8 (3)
9.8 (3)
Standard Piping Length
ft. (m)
24.6 (7.5)
24.6 (7.5)
24.6 (7.5)
24.6 (7.5)
Max. outdoor-indoor height difference
(OU higher than IU)
ft. (m)
49 (15)
49 (15)
98 (30)
98 (30)
Max. outdoor-indoor height difference
(IU higher than OU)
ft. (m)
49 (15)
49 (15)
65.3 (20)
65.3 (20)
Max. Piping Length with no additional
refrigerant charge per System
(Standard Piping length)
ft. (m)
24.6 (7.5)
24.6 (7.5)
24.6 (7.5)
24.6 (7.5)
Total Max. Piping Length per system
ft. (m)
98 (30)
98 (30)
98 (30)
98 (30)
Additional refrigerant charge
(between Standard – Max piping length)
Oz/ft
(g/m)
0.161 (15)
0.161 (15)
0.32 (30)
0.32 (30)
Suction Pipe (size - connection type)
In (mm)
3/8” (9.52)
1/2” (12.7)
5/8” (15.9)
5/8” (15.9)
Liquid Pipe (size - connection type)
In (mm)
1/4” (6.35)
1/4” (6.35)
3/8” (9.52)
3/8” (9.52)
Refrigerant Type
Type
R410A
R410A
R410A
R410A
Refrigerant Heat Pump Models Charge Amount
ozs (kg)
56.44 (1.6)
56.44 (1.6)
91.7 (2.60)
104.1 (2.95)
UNIT SIZE
TOTAL LINE
LENGTH FT (M)
ADDITIONAL CHARGE, OZ/FT. FT (M)
Min
Max
10-25
(3-8)
>25-98
(8-30)
9
10 (3)
98 (30)
None
0.16
12
18
0.32
24
